<%@ page language="java" contentType="text/html; charset=UTF-8"
	pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<style>
* {
	margin: 0;
	padding: 0
}

.box {
	width: 500px;
	height: 300px;
	border: 1px solid #ccc;
	margin: 100px auto;
	padding: 5px;
}

.inner {
	width: 500px;
	height: 300px;
	position: relative;
	overflow: hidden;
}

.inner img {
	width: 500px;
	height: 300px;
	vertical-align: top
}

ul {
	width: 1000%;
	position: absolute;
	list-style: none;
	left: 0;
	top: 0;
}

.inner li {
	float: left;
}

ol {
	position: absolute;
	height: 20px;
	right: 20px;
	bottom: 20px;
	text-align: center;
	padding: 5px;
}

ol li {
	display: inline-block;
	width: 20px;
	height: 20px;
	line-height: 20px;
	background-color: #fff;
	margin: 5px;
	cursor: pointer;
}

ol .current {
	background-color: red;
}

#arr {
	display: none;
}

#arr span {
	width: 40px;
	height: 40px;
	position: absolute;
	left: 5px;
	top: 50%;
	margin-top: -20px;
	background: #fff;
	cursor: pointer;
	line-height: 40px;
	text-align: center;
	font-weight: bold;
	font-family: '黑体';
	font-size: 30px;
	color: #000;
	opacity: 0.5;
	border: 1px solid #fff;
}

#arr #right {
	right: 5px;
	left: auto;
}
</style>

</head>
<body>
	<div class="box" id="box">
		<div class="inner">
			<!--轮播图-->
			<ul>
				<li><a href="login.jsp"><img src="images/login/timg.jpg" alt="" title="登录后可查看蛋糕详情"></a></li>
				<li><a href="login.jsp"><img src="images/login/timg.gif" alt="" title="登录后可查看蛋糕详情"></a></li>
				<li><a href="login.jsp"><img src="images/login/timg (1).jpg" alt="" title="登录后可查看蛋糕详情"></a></li>
				<li><a href="login.jsp"><img src="images/login/timg (2).jpg" alt="" title="登录后可查看蛋糕详情"></a></li>
				<li><a href="login.jsp"><img src="images/login/timg (3).jpg" alt="" title="登录后可查看蛋糕详情"></a></li>
                <li><a href="login.jsp"><img src="images/login/timg (4).jpg" alt="" title="登录后可查看蛋糕详情"></a></li>
				<li><a href="login.jsp"><img src="images/login/timg (5).jpg" alt="" title="登录后可查看蛋糕详情"></a></li>
				<li><a href="login.jsp"><img src="images/login/timg (6).jpg" alt="" title="登录后可查看蛋糕详情"></a></li>
				<li><a href="login.jsp"><img src="images/login/timg (7).jpg" alt="" title="登录后可查看蛋糕详情"></a></li>
				<li><a href="login.jsp"><img src="images/login/timg (8).jpg" alt="" title="登录后可查看蛋糕详情"></a></li>
				<li><a href="login.jsp">去登录</a></li>
			</ul>

			<ol class="bar">

			</ol>
			<!--左右焦点-->
			<div id="arr">
				<span id="left"> < </span> <span id="right"> > </span>
			</div>

		</div>
	</div>
	<script>
		/**
		 *
		 * @param id  传入元素的id
		 * @returns {HTMLElement | null}  返回标签对象，方便获取元素
		 */
		function my$(id) {
			return document.getElementById(id);
		}

		//获取各元素，方便操作
		var box = my$("box");
		var inner = box.children[0];
		var ulObj = inner.children[0];
		var list = ulObj.children;
		var olObj = inner.children[1];
		var arr = my$("arr");
		var imgWidth = inner.offsetWidth;
		var right = my$("right");
		var pic = 0;
		//根据li个数，创建小按钮
		for (var i = 0; i < list.length; i++) {
			var liObj = document.createElement("li");

			olObj.appendChild(liObj);
			liObj.innerText = (i + 1);
			liObj.setAttribute("index", i);

			//为按钮注册mouseover事件
			liObj.onmouseover = function() {
				//先清除所有按钮的样式

				for (var j = 0; j < olObj.children.length; j++) {
					olObj.children[j].removeAttribute("class");
				}
				this.className = "current";
				pic = this.getAttribute("index");
				animate(ulObj, -pic * imgWidth);
			}

		}

		//设置ol中第一个li有背景颜色
		olObj.children[0].className = "current";
		//克隆一个ul中第一个li,加入到ul中的最后=====克隆
		ulObj.appendChild(ulObj.children[0].cloneNode(true));

		var timeId = setInterval(onmouseclickHandle, 2000);
		//左右焦点实现点击切换图片功能
		box.onmouseover = function() {
			arr.style.display = "block";
			clearInterval(timeId);
		};
		box.onmouseout = function() {
			arr.style.display = "none";
			timeId = setInterval(onmouseclickHandle, 1000);
		};

		right.onclick = onmouseclickHandle;
		function onmouseclickHandle() {
			//如果pic的值是5,恰巧是ul中li的个数-1的值,此时页面显示第六个图片,而用户会认为这是第一个图,
			//所以,如果用户再次点击按钮,用户应该看到第二个图片
			if (pic == list.length - 1) {
				//如何从第6个图,跳转到第一个图
				pic = 0;//先设置pic=0
				ulObj.style.left = 0 + "px";//把ul的位置还原成开始的默认位置
			}
			pic++;//立刻设置pic加1,那么此时用户就会看到第二个图片了
			animate(ulObj, -pic * imgWidth);//pic从0的值加1之后,pic的值是1,然后ul移动出去一个图片
			//如果pic==5说明,此时显示第6个图(内容是第一张图片),第一个小按钮有颜色,
			if (pic == list.length - 1) {
				//第五个按钮颜色干掉
				olObj.children[olObj.children.length - 1].className = "";
				//第一个按钮颜色设置上
				olObj.children[0].className = "current";
			} else {
				//干掉所有的小按钮的背景颜色
				for (var i = 0; i < olObj.children.length; i++) {
					olObj.children[i].removeAttribute("class");
				}
				olObj.children[pic].className = "current";
			}
		}
		left.onclick = function() {
			if (pic == 0) {
				pic = list.length - 1;
				ulObj.style.left = -pic * imgWidth + "px";
			}
			pic--;
			animate(ulObj, -pic * imgWidth);
			for (var i = 0; i < olObj.children.length; i++) {
				olObj.children[i].removeAttribute("class");
			}
			//当前的pic索引对应的按钮设置颜色
			olObj.children[pic].className = "current";
		};

		//设置任意的一个元素,移动到指定的目标位置
		function animate(element, target) {
			clearInterval(element.timeId);
			//定时器的id值存储到对象的一个属性中
			element.timeId = setInterval(function() {
				//获取元素的当前的位置,数字类型
				var current = element.offsetLeft;
				//每次移动的距离
				var step = 10;
				step = current < target ? step : -step;
				//当前移动到位置
				current += step;
				if (Math.abs(current - target) > Math.abs(step)) {
					element.style.left = current + "px";
				} else {
					//清理定时器
					clearInterval(element.timeId);
					//直接到达目标
					element.style.left = target + "px";
				}
			}, 10);
		}
	</script>

</body>
</html>